DownTime100HDR

### 1) Overview
 The `DownTime100HDR` table serves as the header-level registry for "100% Downtime" recording. It captures shift-specific and machine-specific metadata for production periods where downtime is logged. This table is primarily utilized in Overall Equipment Effectiveness (OEE) calculations and concise downtime reporting to provide context (date, shift, machine, and production type) for detailed downtime reason codes stored in the associated detail table (`DownTime100DTL`).
 
 ### 2) Column Dictionary
 
 | Column | Type | Nullable | Meaning | Allowed Values | SQL Usage |
 | :--- | :--- | :--- | :--- | :--- | :--- |
 | **index** | integer | No | Internal primary identity for the record. | | Primary Key |
 | **compcode** | string | No | Unique identifier for the company/unit. | "DAS", "HFL", "BPL" | Join key to most tables |
 | **prodno** | integer | No | Unique production transaction number. | | Join key to Detail tables |
 | **proddate** | datetime | No | The actual date the production activity occurred. | | Filtering / Reporting |
 | **shift** | string | No | Shift designation during which the downtime occurred. | "A", "B" | Reporting |
 | **shifthrs** | number | No | Total scheduled hours for the specified shift. | 9.5, 10.0, 11.3, 12.0 | OEE Calculations |
 | **mccode** | string | No | Unique identifier for the machine or work center. | "CNC4", "MAY", "KJ250" | Join to `machine` |
 | **username** | string | Yes | The system user who created or last modified the record. | "system", "punit", "sunil" | Audit trail |
 | **remarks** | string | Yes | General notes or descriptions regarding the production header. | | Documentation |
 | **location** | string | Yes | Physical plant location or factory section code. | | Join to `location` |
 | **ProdType** | string | Yes | Categorization of the production operation stage. | "IstOPR", "IIndOPR" | View Filtering |
 | **slipno** | string | Yes | Reference to a physical production slip or document number. | | Cross-reference |
 
 ### 3) Relationships & Join Map
 
 #### Logical Primary Key
 * **prodno** + **compcode**: Used as the functional unique identifier across production modules.
 
 #### Authoritative Joins (per SCHEMA_MAP)
 * **DownTime100DTL**: Joins on `prodno` and `compcode`. This is the direct 1-to-Many relationship for downtime reason details.
 * **machine**: Joins on `mccode` and `compcode`. Used to retrieve machine names and capacity for OEE reports.
 * **PhyLocation**: Joins on `location` and `compcode` (and optionally `username`).
 * **location**: Joins on `location` and `compcode` for site-specific reporting.
 
 #### Likely Joins (Inferred from Usage)
 * **downtimemas**: Linked indirectly via `DownTime100DTL.downtimereason` to `downtimemas.downcode`.
 * **product1 / product2**: Linked via `prodno` and `compcode` in production analysis views to compare active production time vs. downtime.